The abduction of a witness in a human rights case raises old fears. But some contend it was a political stunt.

The question is reverberating here in the mysterious case of Luis Gerez, a witness in a human rights trial who went missing last month and reappeared two days later, shirtless and in shock, saying he had been kidnapped, tied up, beaten and burned with cigarettes.

The case has raised troubling questions in a nation still torn by memories of a brutal military dictatorship that ended almost a quarter of a century ago, leaving as many as 30,000 people dead or "disappeared."

Many had hoped that kidnappings as a means of political coercion were a thing of the past.

In a nation inured to political skulduggery, denial and disinformation, the disappearance and reemergence of Gerez has spawned sinister theories. Most center on the actions of President Nestor Kirchner, who has made punishing past military abusers a focus of his administration, and who intervened directly in the case.

Gerez, whose testimony in 2005 about being tortured during the dictatorship helped banish a powerful former police official from Congress, said he was abducted Dec. 27 while walking to a grocery store near his home north of the capital.

He said men forced him into a vehicle and drove him to a warehouse or a shed, where he was kept hooded.

"I thought they were going to kill me," he told investigators, recalling a moment when he could hear a gun being cocked.

The incident came a few months after the unsolved disappearance of another human rights figure, Jorge Julio Lopez, whose testimony last year helped send a former provincial police chief to jail for life.

Lopez has been called the first desaparecido, or disappeared, since the return of democracy to Argentina. Police fear that he was killed.

Lopez, like Gerez, was a construction worker and onetime left-wing activist.

President speaks out

The disappearance of Gerez, 51, apparently so alarmed Kirchner that he took the unusual step of going on television and radio on Dec. 29 to denounce it. The president blamed "paramilitary and parapolitical elements" for the disappearance.

"We are not going to surrender to extortion," Kirchner said.

Less than an hour after Kirchner's address, Gerez reappeared on a suburban street in the neighborhood where he said he had been kidnapped. He was dazed but in good health.

"Mr. President, I owe you my life," Gerez told the local media. Gleeful presidential aides said Kirchner's words had spooked the bad guys.

The political triumphalism was too much for an opposition scrambling to find an alternative to Kirchner in national elections scheduled for this year.

Critics suggested that the incident was staged to enhance the carefully crafted crusader image of Kirchner, who has pushed to nullify amnesties given to suspects from the former dictatorship's "dirty war" against perceived enemies.

Gerez's status as an avid Kirchner supporter stoked suspicions.

"A fabrication," said former President Carlos Menem, a fierce Kirchner rival from the right.

Others have suggested that the president's underlings might have faked the episode without his knowledge.

Kirchner "was sold a novel and he bought it, and now he has to take the responsibility for that," Luis Patti, a retired police inspector, told a radio station.

It is not lost on observers that Patti may have a grudge to bear and a reputation to defend.

In congressional testimony in 2005, Gerez identified Patti as a torturer, prompting lawmakers to deny the former police official a congressional seat that he had won at the ballot box.

A suspect

Now a powerful right-wing political figure, Patti became a suspect in Gerez's alleged disappearance.

He denied any connection.

"I have the tranquillity to say that it wasn't anyone in my party or my entourage that committed this," Patti told reporters. "Behind all this there is a reason, and it is political," he said, alluding to the president's office.

One of Gerez's six children, Jose Luis Gerez, doubted that Patti was behind the incident.

"They would have killed my old man," he told the weekly Perfil newspaper. "He would have appeared dead."

Kirchner's aides have strongly denied that Gerez's abduction was staged. Prosecutors say his story is supported by physical indications that he had been tied and abused, and evidence of psychological trauma.

Authorities said about 4,000 police officers assigned to the case had been unable to find any abductors or the site where Gerez said he was held.

"We have evidence that he had been kidnapped," prosecutor Facundo Flores told reporters recently. "It is not the time to doubt someone who for us today is a victim."

Gerez has been in seclusion and under police protection. He told authorities that he had received other threats recently -- someone slashed his car tires; a motorist on the highway brandished a pistol at him; and a man in a suit carrying a briefcase approached him at a bus stop and told him that he knew where he and his family lived.

Gerez said he never saw the faces of his abductors and had few words with them. It is still unclear whether the kidnappers gave Gerez any clues about why he had been targeted or why he was released.